Noiseless fan.



c. e. SWENSON.

NOISELESS, FAN.

APPLICATION FILED JAN.25, 1911.

1 ,241 1 669. I Patented Sept. 25, 1917.

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WITNESSES: v l/VI/E/VTOR QSwe/ wn,

v S i To all whom it mag) concern:

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,CARL G. SWENSON, 0F INDIANAPOLIS, INDIANA, ASSIGNOR TO THE OAKES COMPANY, OF INDIANAPOLIS, INDIANA, A CORPORATION OF INDIANA.

NOISELESS FAN.

Be it known that I, CARL G. SwENsoN, a citizen of the United States, residing at Indianapolis, in the county of Marion and State of Indiana, have invented a new and useful N oiseless Fan, of which the following is a specification.

It is the object of my present invention to produce a noiseless fan. v

The accompanying drawing illustrates my invention. Figure 1 is an elevation of a four-bladed fan embodying my invention; and Fig. 2 is an under plan view on a somewhat larger scale.

The fan shown has a plurality "of blades 10 mounted on a central spider 11. These blades are preferably made of sheet metal, as is clear from Fig. 2, and are conveniently fastened to the spider by rivets. The blades 10 are skewed as a whole, and are preferably concave on the air'pushing side, so as to give the air a gradual acceleration. At its advancing edge, each blade 10 is folded back on itself conveniently on the pushing face to form a lap 13, which at its rear edge lies close to the body of the blade, as is clear from Fig. 2. In this way, a blunt, rounded advancing edge 14: is formed on each fan blade, and by reason of this blunt, rounded advancing edge it is found that the noise usually incident to fans is practically wholly eliminated.

I claim as my invention:

l. A sheet metal fan blade having a con Specification of Letters Patent.

cave air-pushing face, said'fan bladecomprising a single piece of sheet metal which.

at the rear edge is of but a single thickness but is folded back on itself at the advancing edge.

2. A sheet metal fan blade having a concave air-pushing face, said fan blade comprising a single piece of sheet metal'which at the rear edge is of but a single thickness but is folded back on itself at the advancing edge to form a blunt rounded fold.

3. -A sheet metal fan-blade havinga concave air-pushing face, said fan blade comprising a single piece of sheet metal which at the rear edge is of but a single thickness but is folded back on itself on the pushing face at the advancing edge.

4. A sheet metal fan blade, said fan blade comprising a single piece of sheet metal which at the rear edge is of but a single thickness but is folded back on itself on the pushing face at the advancing edge.

5. A sheet metal fan blade havin a concave air-pushing face, said fan bla e comprising a single piece of sheet metal which at the rear edge is of but a single thickness but is folded back on itself on said concave face at the advancing edge to form a blunt rounded fold. 1

In witness whereof, I have hereuntoset my. hand at Indianapolis, Indiana, this 19th day of January, A. D. one thousand nine hundred and seventeen.

CARL G. SWENSON.

ratentea'sept. 25.1mm

I Application filed January 25, 1917. Serial No. 144,336. 

